Case Report: A case study and literature review of diffuse large B-cell lymphoma presenting as a primary uterine mass with appendiceal involvement and an 11q gain

Context Primary lymphoma of the uterine corpus is an exceptionally uncommon form of extranodal lymphoma that is often mistaken for uterine sarcoma or carcinoma. We present a case of primary diffuse large B-cell lymphoma (DLBCL) of the uterus, with appendiceal involvement and a gain at 11q23.3/11q24.3 without MYC rearrangement. The characteristic distal 11q loss required for the diagnosis of high-grade B-cell lymphoma with 11q aberration was not demonstrated; the tumor was therefore classified as DLBCL, NOS with an 11q gain. In addition, we review 34 documented cases from 1965 to 2025 that include comprehensive clinicopathological information. Findings A 56-year-old female patient presented with a rapidly growing abdominal mass and compressive symptoms. Imaging revealed marked uterine enlargement (>15 cm) and a separate appendiceal mass. Histological analysis identified a germinal center B-cell-like DLBCL (CD20 + , CD10 + , Bcl-6 + , MUM-1 − , Ki-67 90%), and FISH analysis demonstrated gains at 11q23.3/11q24.3 without MYC rearrangement. After surgery, the patient began R-CHOP chemotherapy. Among the 34 reviewed cases, the median age was 56 years (range 3.5–84); common symptoms included abnormal vaginal bleeding (56%), pelvic mass (47%), and abdominal pain (41%). DLBCL accounted for 74% of cases (GCB subtype 15%, non-GCB 41%). Uncommon subtypes included NK/T-cell lymphoma (6%), peripheral T-cell lymphoma (6%), myeloid sarcoma (3%), indolent T-cell lymphoproliferative disorder (3%), and others. Treatment approaches have shifted from surgery alone to surgery plus R-CHOP, which was used in 50% of recent cases; however, comparative survival could not be assessed from these descriptive data. The combination of 11q alteration with appendiceal involvement appears not to have been previously reported; however, this observation is descriptive and does not by itself establish a distinct diagnostic entity. In summary Diagnosing primary uterine lymphoma presents considerable challenges. Our case draws attention to a gain at 11q23.3/11q24.3 as a molecular feature of uncertain significance and highlights the value of a multidisciplinary care approach. Systematic chemotherapy, particularly R-CHOP, is the mainstay of current treatment for DLBCL, although comparative efficacy could not be assessed from the reviewed cases.